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J. W. BURNS.

TWO-CYCLE RECIPROCATING ENGINE.

APPLICATSON FILED SEPT 5. I9I8.

Pzficn'tod July 22, 1919.

2 SHEETS--SHEET l.

l'nven i302" Lfohn WEurns 725$ .Aliiaznew O jacket spaces.

JOHN W. BURNS 0F LOSANG-ELES, CALIFORNIA, ASSIGNOR OF ONE-THIRD TO RUFUS A. HOLT AND ONE-THIRD FORNIA.

TO JOSEPH W. HARASTA, BOTH OF LOS ANGELES, CALI- TWO-CYCLE RECIPROCATING ENGI NE Specification of Letters Patent; Patented July 22, 1919.

Application filed September 5, 1918. Serial No. 252,713.

- To all whom it may concern:

Be it known that citizen of the United States, Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Two-Cycle Reciproresiding at Los eating Engines, ofwh ich the following is a specliication. I

Thisinvention relates to a two cycle internal combustion engine, in which posi-, -.t1vely actuated valves are used. to control the lnlets and exhaust.

Twocycle engines are more desirable than four cycle, because of the more even flow of power per stroke, a less weight of engine 'per' unit of output, more p'erfect'balance,

' structed, the two and quicker acceleration. As'at present concycle engine is less desirable than the four cycle because of its lower efficiency.

It is common practice to construct two cycle gas engines with inlet and exhaust so that they may be adjusted.

' I- accomplish these objects bymeans of ports in each 'the em cylinder which are opened and closed by'the piston. With such construction, no provision is made for adjustment of the events of a cycle. It is obvious-thatadjustment of the eventsgisdesirable. It is an .obJect of this cycle reciprocating gas engine with posi invention to' provide a two tively actuated valves, which are arranged I bodimentsof my invention illustrated in the accompanyingdrawing, in which:

Figure -1 is a front elevatlon of a four cylinder engine constructed according to my invention. Fig. 2 is a side elevation partly a are the cylinders,

in section of one of the cylinders and crank .case. Fig. '3 is a section as seen on the line 33 of Fig.2, and'Fig. 4 is an enlarged fragmentary section through the piston rod at the point of its attachment to the yoke.

Referringparticularly tothe drawings, A B the crank case, 0 the carbureter, D the inlet manifold, and E the exhaust manifold. The cylinders are duplicates of eachother,

and one will ticularly to has .a' body 5 be' described. iR-eferrin par-' Figs. .2, 3. and 4, the cy inder provided withthe usual water. A lateral flange 6 is provided at the crank end for attachment of the cylinder to the crank case. Just above the flange is a lateral port 7, whiclf communi- I, JOHN W. BURNS, a

, chamber,

' Adjacent its lower which extends laterally thereof and has its cates with a by pass 8 extending longitudinally of the cylinder. Projecting from the cylinder opposite to the port 7 is an extension 9, which has a port 10 leading into a valve chamber formed in the extension. A plug 11 closes the valve chamber on its, upper side and provides means of access to the chamber. On the lower side of the valve a valve seat is formed, and disposed thereon is a lift valve 12. On the lower side of the valve 12 is an inlet port 13 extending laterally and communicatin with the inlet manifold D.

Secured on'the top of the body is a cylinder head 14, in which are mounted the cylinder valves. Communicating with the bypass 8 is a passage 15, which leads to a valve chamber. Mounted in the valve chamber is a valve cage 16, which is held in position by a plug 17. The valve cage forms a seat for a valve 18. A port 19 leads to a valve chamber in which isdisposed a valve cage 20. Valve cage20 is similar to valve cage 16 and is held in position by asiinilar plug. Seated on haust valve 21. j In an'opening formed on the upper side of the crank case B is a rabbet 22. The cyl- ,lIlClGl is mounted upon the crank case and bolted thereto, a crank head 23 being clamped between, the cylinder and case and being packed -by a copper gasket 24.

Formed on the crank head is a gland con? the valve cage is an exstruction 25, through which the piston rod 4 may pass. The body of the crank case is closed by\a bottom 27 and is formed so as to.be oil tight. The body is offset as indicated by 28 to form a space for the valve .cams and shaft.

Disposed within thecylinder is a piston 29 provided with the usual packing and having oil ducts 30 leading from the piston rod to the periphery. A hollow piston rod 31 closed at the head end is securedyto the piston and held in position by a nut 32. Perforations 33 connect the interior of the ton rod extends through the gland 25 in the crank head, and is suitably packed therein.

end'is a dipper pipe 34,

piston rod with the oil ducts 30. The pisa yoke 36, which slides on guides 37 and 38? mounted on the sides of the crank case. Slidingly mounted in the slot in the yoke is a crank pin bearing 39, to which is secured a crank arm 40 on the crank shaft.

The inlet valve 12 has a stem 41, and mounted thereon is a compression spring 42, which tends to hold the valve 12 on its seat. Th valve stein extends through a guide plug 43 into the crank case and has a tappet 44 mounted on the lower end. The tappet rides upon a cam 45 mounted on cam shaft 46. Cam shaft 46 is operated from the en'- gine shaft by means of-intermediate gearing indicated in dotted lines, and so proportioned that the ratio of gearinv is one to one. This gearing may be of any well known type and is not shown in detail. Cylinder inlet valve 18 has a stem 47, which is slidingly mounted in the cage 16. A com.- pression sprincr 48 tends to hold valve 18 upon its seat. lVlounted upon the top of the cylinder head is a standard 49, upon which is pivotally mounted a lever 50 engaging the valve stem 47. Engag ng the other end of lever 50 is a push rod 51, which extends into the crank case and has a ta-ppet actuated by a cam upon cam shaft 46. Exhaust-valve 21 .issimilar in construction to the inlet valve for the cylinder and operated by similar mechanism. As shown in Fig. 3, valve 21 has a valve stem 52,.which is actuated by a lever 53 (see Fig. 1) mounted upon stand-' ard 49. A push rod 54 extends into the crank case and is operated from the cam shaft 46.

The crank caseisfilled with oil, and

I upon each down stroke of the piston, the v dipper 34 enters the oil bath, some of the oil passing beyondthe check valve and into the hollow iston rod. The oil then travels up the ro through the perforations 33,

into'tl1e oil ducts 30, and to the periphery valve 18 is closed at about eighteen degrees.

of the piston upstroke,and the charge compressed in the cylinder abov the piston.

At the beginning of the down stroke, th

charge is fired, then the exhaust valve 21 opens when the piston is about 45 degrees from the bottom of its stroke to permit the escape of burnt ases. Just after the intake valve is op'enec the exhaust valve 21 is closed. There is an overlap of the opening of the exhaust and intake valves permitting scavenging.

It is obvious that the events of the stroke can be varied by adjusting the cams on the cam shaft. It is also obvious that with the use of positively actuated valve that these events may be made sharp, opening and closing of the valve occurring almost 1nstantly.

Another advantage this type of engine has over the ordinary two cycle gas engine compressing the charge in the crankcase is a higher carburation. Where the charge is drawn into the crank case, there is arelatively large clearance space permitting expansion and contraction of the gas and vapor contained therein. This results in a low suction. With my construction the clearance space is reduced to a minimum producing a better carburation due to the increased suction. With my improved engine, it is not necessary to makethe crank case gas tight, and by the use of a scotch yoke insteadof a connecting rod, I am able' to construct a better balanced motor.

lVhat I claim is: v

1. A two cycle internal combustion engine comprising a cylinder, a piston the re in, said'c-ylinder having both ends-closed and being provided with an inlet communieating with one end thereof and a bypass communicating with both ends, a valve controllincr the flow of gas to said inlet, a valve controlling the flow of gas through said bypass, a valve controlling th exhaust, and means to positively actuate all of said valves and capable of varying the events. 2.- A two cycleinternal combustion engine comprising a cylinder, a piston therein,

said cylinder having its crank endclosed-by' a, head and being provided with an inlet communicating with the crank end and a bypass leading therefrom 'to the head end, a valve controlling the flow of gas to said inlet, a valve controlling th flow of gas through said bypass, a valve controlling the exhaust, and means to positively. actuate all of saidvailves and capable of varying the events. A

In witness that I claim the foregoing I have hereunto subscribed my name this 26th day of August, 1918.

JOHN W. BURNS. 

